MILLIONS of Scottish Power customers face a major price hike after the energy giants revealed plans to increase gas bills by an average of 19 per cent and electricity by 10 per cent.

Some 2.4 million customers will be hit by the price rise which comes into force on August 1.

Households on a dual fuel tariff paying monthly by direct debit will see their bills increase by an average of £175 a year.

The company last put its prices up in November, when gas prices rose two per cent and electricity bills by 8.9 per cent.

It blamed the most recent price rise on a prolonged rise in wholesale energy costs, which has pushed the average price of wholesale energy up 30 per cent since November.

Other suppliers are widely expected to follow Scottish Power's lead over the coming weeks.

All of the big six companies raised their prices over the winter and another wave of hikes is currently expected as wholesale energy costs continue to rise.

The Bank of England has said it expects fuel bills could rise by as much as 15 per cent by the end of the year and British Gas owner Centrica has also signalled that price rises are on the way.

Scottish Power added that the rising cost of meeting Government's environmental and social programmes and of distributing electricity via the National Grid, had also contributed to the price rise.

Raymond Jack, Scottish Power's UK retail director, said: "Wholesale prices for gas and electricity have increased significantly since the end of last year and continuing unrest in global energy markets means future prices are volatile.

"We understand times are difficult for many people, and we have done what we can to absorb these additional costs for as long as possible to minimise the impact on our customers."

Scottish Power, which is part of Spain's Iberdrola, said some 700,000 of its customers will be protected from the price rises through capped or fixed price deals.

It also today launched an online product with a long fixed-price offer that it claims is one of the cheapest in the market.

Scottish Power said it could help its customers to reduce their fuel bills by making energy efficiency savings in their homes.